| // Licensed to the Apache Software Foundation (ASF) under one |
| // or more contributor license agreements. See the NOTICE file |
| // distributed with this work for additional information |
| // regarding copyright ownership. The ASF licenses this file |
| // to you under the Apache License, Version 2.0 (the |
| // "License"); you may not use this file except in compliance |
| // with the License. You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, |
| // software distributed under the License is distributed on an |
| // "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| // KIND, either express or implied. See the License for the |
| // specific language governing permissions and limitations |
| // under the License. |
| |
| package org.apache.impala.analysis; |
| |
| import org.apache.impala.authorization.Privilege; |
| import org.apache.impala.common.AnalysisException; |
| import org.apache.impala.thrift.TFunctionCategory; |
| import org.apache.impala.thrift.TShowFunctionsParams; |
| |
| import com.google.common.base.Preconditions; |
| |
| /** |
| * Representation of a SHOW FUNCTIONS [pattern] statement. |
| * Acceptable syntax: |
| * |
| * SHOW FUNCTIONS |
| * SHOW FUNCTIONS LIKE 'pattern' |
| * |
| */ |
| public class ShowFunctionsStmt extends StatementBase { |
| // Pattern to match tables against. | denotes choice, * matches all strings |
| private final String pattern_; |
| |
| // DB (if any) as seen by the parser |
| private final String parsedDb_; |
| |
| // Category of functions to be shown. Always set. |
| private final TFunctionCategory fnCategory_; |
| |
| // Set during analysis |
| private String postAnalysisDb_; |
| |
| /** |
| * Constructs a show statement which matches all functions against the |
| * supplied pattern. |
| */ |
| public ShowFunctionsStmt(String db, String pattern, TFunctionCategory fnCategory) { |
| Preconditions.checkNotNull(fnCategory); |
| parsedDb_ = db; |
| pattern_ = pattern; |
| fnCategory_ = fnCategory; |
| } |
| |
| /** |
| * Can only be called after analysis, returns the name of the database that |
| * this show will search against. |
| */ |
| public String getDb() { |
| Preconditions.checkNotNull(postAnalysisDb_); |
| return postAnalysisDb_; |
| } |
| |
| public String getPattern() { return pattern_; } |
| |
| @Override |
| public String toSql(ToSqlOptions options) { |
| String fnCategory = (fnCategory_ == null) ? "" : fnCategory_.toString() + " "; |
| if (pattern_ == null) { |
| return "SHOW " + fnCategory + "FUNCTIONS"; |
| } else { |
| return "SHOW " + fnCategory + "FUNCTIONS LIKE '" + pattern_ + "'"; |
| } |
| } |
| |
| @Override |
| public void analyze(Analyzer analyzer) throws AnalysisException { |
| postAnalysisDb_ = (parsedDb_ == null ? analyzer.getDefaultDb() : parsedDb_); |
| if (analyzer.getDb(postAnalysisDb_, Privilege.VIEW_METADATA) == null) { |
| throw new AnalysisException(Analyzer.DB_DOES_NOT_EXIST_ERROR_MSG + postAnalysisDb_); |
| } |
| } |
| |
| public TShowFunctionsParams toThrift() { |
| TShowFunctionsParams params = new TShowFunctionsParams(); |
| params.setCategory(fnCategory_); |
| params.setDb(getDb()); |
| params.setShow_pattern(getPattern()); |
| return params; |
| } |
| } |